Weight unit for gymnastic apparatus

ABSTRACT

In a gymnastic apparatus the weight unit ( 11 ) is provided with a stack ( 19 ) of plates ( 20 ) formed by multiple plates ( 20 ) placed one on top of the other and having a longitudinal symmetric axis ( 14 ); a guide column ( 12 ) coaxial to the axis ( 14 ) engaged by the plates ( 20 ) with possibility of movement.

[0001] The present invention refers to a weight unit for a gymnastic apparatus.

[0002] In particular, the present invention refers to weight unit for a gymnastic apparatus used to train anterior thigh muscles, commonly defined as “leg extension apparatus”; the following description continues with reference to the aforementioned term, without losing its general character.

[0003] In the field of gymnastic apparatuses, a leg extension apparatus is provided with a weight unit generally comprising a portal frame composed of two parallel uprights, two horizontal parallel crosspieces extending between the uprights transversally to the uprights, and two vertical guide columns guides extending between the crosspieces parallel to the two uprights.

[0004] The weight unit is provided with a stack of plates having a longitudinal symmetric axis between the guide columns and formed by multiple plates placed one on top of the other with possibility of movement along the guide columns.

[0005] A serious inconvenience of weight units of known type as illustrated above is represented by the fact that the portal frame comprises a relatively high number of components, that is to say two vertical uprights, two horizontal crosspieces and two vertical guide columns, thus requiring a relatively long, complex and expensive sequence of constructive operations.

[0006] The purpose of the present invention is to obtain a weight unit for a gymnastic apparatus without the aforementioned drawbacks.

[0007] According to the present invention, the weight unit for a gymnastic apparatus comprises a stack of plates with longitudinal symmetric axis formed by multiple plates placed one on top of the other; being characterised by the presence of a first guide column coaxial to the axis engaged by the plates with possibility of movement.

[0008] The description of the invention continues with reference to the enclosed drawings of a non-restrictive embodiment, whereby:

[0009]FIG. 1 is a diagrammatic perspective view of a gymnastic apparatus provided with a preferred embodiment of the weight unit of the invention;

[0010]FIG. 2 is a diagrammatic side view, with cross-sectioned parts and removed parts, of the weight unit of FIG. 1;

[0011]FIG. 3 is a diagrammatic perspective view of a first detail of FIG. 2; and

[0012]FIG. 4 is a diagrammatic perspective view of a second detail of FIG. 2.

[0013] With reference to FIG. 1, number 1 indicates a gymnastic apparatus for anterior thigh muscles, referred to in the following description as “leg extension apparatus”.

[0014] The leg extension apparatus 1 is provided with a base 2, which is used to place the leg extension apparatus 1 on the ground; and a support device 3 for the user that comprises a seat 4 and a backrest 5 extending upwards from the base 2.

[0015] The leg extension apparatus 1 is also provided with a lifting device 6 comprising a fixed column 7 that extends upwards from the base 2, and a support arm 8, which is fitted to the column 7 to oscillate around a basically horizontal axis 9, is provided with a padded roll 10 that that projects from the arm 8 parallel to the axis 9 and is moved by the user from the initial lowered position (FIG. 1) to final raised position (not shown) against the resistance of the force applied on the arm 8 by a weight unit 11.

[0016] With reference to FIGS. 2 and 3, the unit 11 comprises a guide column 12, which extends in vertical direction 13, has a longitudinal symmetric axis 14 parallel to direction 13, has a basically elliptical transversal cross-section and comprises two tubular profiles 15 extending upwards from a support plate 16 anchored to the base 2 and provided with a partition 17 that extends between the profiles 15 and arranged on opposite sides of the axis 14 to define a channel 18 basically coaxial to axis 14.

[0017] Moreover, the weight unit 11 is provided with a stack 19 of metal plates 20 formed by basically cylindrical multiple plates 20 (FIG. 4) that are placed one on top of the other in direction 13, engage the column 12 in a fixed angular position with possibility of movement, and have a hole 21 through the plate 20 transversally to direction 13.

[0018] The bottom of the stack 19 is supported by multiple springs 22 (four springs 22 in the example), which are distributed around the axis 14 and inserted into guide pins 23 that extend upwards from the plate 16 parallel to direction 13. According to embodiments not shown in the enclosed figures, the transversal cross-section of the column 12 can have a different configuration from the one illustrated in the enclosed figures, so as to prevent the plates 20 from rotating around the axis 14.

[0019] The plates 20 are connected to the arm 8 and the roll 10 by means of a driving means 24 comprising a cam (not shown) housed inside the base 2 and splined to a first shaft (not shown) that extends parallel to direction 13, is housed inside the column 7 with possibility of rotation and engaged to a second shaft (not shown) coaxial to axis 9 by a gear (not shown) and engaged in fixed angular position through the arm 8.

[0020] The cam (not shown) is connected by means of a traction cable 25 of known type to a rod 26, which is part of the lifting device 6, is fitted to the plates 20 with possibility of movement, has multiple holes 27 uniformly distributed along the rod 26 and made through the rod 26 transversally to direction 13 and is axially blocked on one of the plates 20 by means of a locking pin 28.

[0021] The cable 25 is wound around multiple pulleys 29, one of them being illustrated in FIG. 2, and is fitted with possibility of rotation to a support bracket 30 that extends upwards from a flat plate 31 fixed to the free upper end of the column 12.

[0022] Finally, the weight unit 11 is provided with an additional guide column 32 comprising a basically cylindrical tubular body 33 made of transparent material, which extends around the plates 20 in coaxial position to axis 14 and is engaged to the plates 20 with the possibility of movement.

[0023] The body 33 has a slot 34 through the body 33 parallel to direction 13, which is engaged by the pin 28 during use. The upper free end of the body 33 is closed by a cover 35 fixed to the annular border 36 that projects upwards from the plate 31 in coaxial position to axis 14.

[0024] The operation of the leg extension apparatus 1 can be easily deduced from the aforementioned description and requires no further explanations. 

1) Weight unit for a gymnastic apparatus comprising a stack (19) of plates (20) with longitudinal symmetric axis (14) formed by multiple plates (20) placed one on top of the other; being characterised by the presence of a first guide column (12) coaxial to the axis (14) and engaged by the plates (20) with possibility of movement. 2) Weight unit as defined in claim 1, in which the first column (12) extends through the plates (20). 3) Weight unit as defined in claim 1, in which the first column (12) extends around the plates (20). 4) Weight unit as defined in any of the foregoing claims, comprising a lifting device (6) of the plates (20) composed of a rod (26) in basically coaxial position to the axis (14) suitable to engage the plates (20) with possibility of movement; a locking pin (28) to block the rod (26) in axial position on one of the plates (20); at least one pulley (29); and at least a traction cable (25) wound around the pulley (29) and hooked to the rod (26). 5) Weight unit as defined in claim 4, in which the pulley (29) is fitted to the first column (12) with possibility of rotation. 6) Weight unit as defined in claim 4 or 5, in which the first column (12) extends through the plates (20) and has a channel (18) capable of housing the rod (26). 7) Weight unit as defined in claim 6, in which the first column (12) comprises two elongated elements (15) basically parallel to the axis (14) and arranged on opposite sides of the axis (14) to define the channel (18). 8) Weight unit as defined in claim 4 or 5, in which the first column (12) extends around the plates (20) and has a slot (34) through the first column (12) capable of housing the locking pin (28). 9) Weight unit as defined in any of the foregoing claims, in which the first column (12) is engaged by the plates (20) in fixed angular position. 10) Weight unit as defined in any of the foregoing claims, comprising a second guide column (32) coaxial to the axis (14) and engaged by the plates (20) with possibility of movement. 11) Weight unit as defined in claim 10, in which the first and second column (12, 32) extend through the plates (20) and around the plates (20), respectively. 12) Weight unit as defined in claim 10 or 11, in which at least one of the first and second column (12) is engaged by the plates (20) in fixed angular position. 13) Weight unit as defined in any of the foregoing claims, comprising shock-absorbing means (22) capable of supporting the stack (19) of plates (20). 14) Gymnastic apparatus comprising a weight unit as defined in any of the foregoing claims. 